Houston-based Quantum Energy Partners’ new Denver-based energy company plans to buy oil and gas assets in California in a deal that could be worth as much as $742 million.Privately held Sentinel Peak Resources of Denver will buy California onshore assets from the oil and gas subsidiary of Phoenix-based Freeport-McMoRan Inc. (NYSE: FCX) for $592 million. Additionally, Sentinel Peak Resources would pay an extra $50 million per year if oil stays above $70 per barrel in 2018, 2019 and 2020.